He's almost certainly off the wagon. BBC news had some long lens shots of him sitting round a table with Tony, Angela Merkel and some other potentate with his back to the camera.

Bush poured a drink out of a brown bottle into his glass. The foamy head overflowed the top of the glass in a way that only novice drinkers can achieve.

There are only three possibilities:-

1 Dubya is indeed back on the pish
2 He's secretly Dr Jeckyl and his Mr Hyde potion looks like beer
3 He's still dry but didn't want to appear rude when Putin offered him a glass of his home brew 'Chateau Polonium'.

Edited to add ..

I now have nightmare visions of a paralytic president in the Oval Office dressed only in the presidential Y-fronts and being restrained by body guards as he reaches for the big, red button on his desk while shouting 'I'll teach those b@stards to vote for Gore. What's the co-ordinates of California?'.